<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>    
    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>

</head>
<body>
    <div id="app">
       <my-component></my-component>
    </div>
    <div id="app1">
       <my-component></my-component>
    </div>
    <script>
        Vue.component("my-component",{
            template:"<div>我是组件</div>"
        });

        new Vue({
            el:"#app"
        });
        new Vue({
            el:"#app1"
        });
    </script>
</body>
</html>